And spectators found it whenever he played, with his elegant gazelle runs, his leaps and accelerations, his classy back-heels and his long, loping passes from midfield.
To settle the bet, a photographer was ask to photograph a horse galloping and the bet was settled, because you could see that all the hooves were off the ground in some of the photos.
Here's James speaking with sports physiologist, Dr Zoe Saynor, after Zoe had been monitoring James's fitness while running on a treadmill for BBC Radio 4 programme, Inside Science.